Machine for grinding dies.



LE ROY B! FRASER. MACHINE FOR GRINDING DIES.

v APFUCATION FILED MAR- l9). 1 fifi'wfigl Patented Feb. 26, 1918.

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LEROY B. FRASER. MACHINE FOR GRINDING DIES. APPLICATION, FILED MAR-1. 191?.

- Patented Feb 26,1918.

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MACHINE FOR GRINDING DIES.

APPLICATION FILED MAR. 7. 1911.

Patented Feb. 26, 1918..

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IJE- BUY B. FRASER, OF NEW HAVEN, CONNECTICUT, ASSIGNOR T0 SEWELL-CLAPP ENVELOJPES, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

MACHINE FUR GRINDING JDIES.

To all whom it'may concern: I

Be it known that I, LE For B. FRASER, a citizen of the United States, and a resident of New Haven, in the county of New Haven and State of Connecticut, have invented certain new and useful Improvements in Machines for Grinding Dies, of which the following is a full, clear, and exact speclfication.

My invention is concerned with a machine for grinding dies, such for instance as those used in cuttingpaper-envelop blanks, and it is designed to produce a machine of the class described which shall be simple in its construction and which can be conveniently and readily used for sharpening such dies.

To this end, my invention consists essentially of a horizontal table upon which the base ofthe die rests so that it can be freely moved around to bring all its edges into proper relationship with the grinding belt without raising the die from the table while it is being ground, in combination with an endless abrasive belt running through the table substantially at right angles thereto, together with guide rollers for the belt above and below the table and controlling its application to the edge of the die, and supporting rollers for the belt, the rotation of one of which serves to drive the belt.

To illustrate m invention, I'annex hereto four sheets 0 drawings, in which the same reference characters are used to designate identical parts in all the figures, of which,-

Figure 1 is a front elevation of a machine embodying my invention;

. Fig. 2 is a perspective new of one form of a paper-envelop cutting die which the machine is designed to grind;

Fig. 3 is a top plan view of the machine with a portion of the table broken out;

Fig. 4 is a side elevation of the same in section on the line 4-4 of Fig. 3;

Fig. 5 is a vertical section on a larger scale, on the line 5-5 of Fig. 3; .Fig. 6 is a similar view, but with the belt aldjusted difierently to grind the mslde of t e die, the adjustment shown in Fig. 5 be- .in to grind the outside;

ig. 7 is a detail in section on the line 77 of Fig. 3, but on the same scale as Flgs. 5 and 6;

Fi 8 is a similar detail, in section on the line 8-8 of Fig. 3;

' Specification of Letters Patent.

Patented Feb. as, rare.

' Application filed March 7, 1917. Serial No. 153,186.

Fig. 9 is a detail in side elevation of the ,central portion of the roller supporting tally movable frame in which the roller support proper is held;

Figs. 11 and 12 are enlarged details of the portion of the frame shown in Fig. 10; and

Fig. 13 is a detail in section on the line 13-13 of Fig.4, but on a larger scale. I

In carrying out my invention in its preferred form, I employ a generally rectangular main frame, which may be built up from suitable angle irons or other structural forms, and has the four legs 20, on the top of which is secured the table 21, which is preferably formed of a rectangular sheet of metal having its edges turned down to form vertical flanges 22, the legs being suitably riveted to the table and braced in any desired manner. At the bottom of the framework, I preferably employ the horizontal longitudinal brace bars 23 and 24, and above these I secure the transverse brace bars 25.

In this main frame, I mount a swinging frame 26, likewise made up of suitable angles or other structural metal forms, the base of this frame being a rectangle, and upon this rectangle I secure the substantially vertically-extending yoke-pieces 27 and 28, which are connected at the top by the base plate 29 of anelectric motor 30, which may be of any desired construction, and which is suitably connected with a power circuit, as indicated diagrammatically in Fig. 3. llhe armature shaft of this motor carries a small driving pulley 31 which is connected by a belt 32 with a pulley or roller 33 secured on one end of the driving shaft 34, which is suitably journaled in bearings formed in or secured to the frame 26. The other end of this driving shaft 34 has secured thereon the belt pulley 35, over which runs the abrasive belt 36, the upper end of which is suptighten or loosen the abrasive belt 36. As seen in Fig. 13, the frame 26 is pivoted at its rear end on the rod 41, which is passed through the ends of the frame 26 and through the ears 42 extending upward from the brace bar 23.

The table 21 has secured to the under side thereof the connected angles or Z-bars 43 which form ways in which slides horizontally the frame 44, which is preferably constructed of a block of wood open in the center, and having the oppositely faced and inwardly projecting lugs 45. These lugs 45 have the channels 46 formed therein, these channels being slightly inclined, as shown, and formed with a somewhat deeper recess 47 at the top. A screw-shaft 48 is secured in the frame 44 so that it can turn freely therein, being held in place by the collars 49. The outer portion of the shaft 48 is threaded through the bar 50 secured inside of the adjacent flange 22, and it is provided at its outer end with the handle 51 by which it can be turned so as to move the frame 44 from the position shown in Fig. 5 to that shown in Fig. 6, or to any desiredintermediate position. The top supporting roller 37 is journaled upon the shaft 52 secured in the top of the fork 53, the bottom of which has the solid rectangular portion 54 provided with the horizontally projecting ears 55 which enter the recesses 47 and hold the fork 53 in place, the sides of the portion 54 entering the grooves or channels 46. The fork 53 also carries the shaft 56 below the shaft 52, and the guide roller 57 is journaled on this shaft. The lower guide roller 58 is supported beneath the table by the shaft 59, which is journaled-in the fork 60, the handle of which has the elongated offset slot 61 therein, through which the set-screws 62 extend and are threaded into the handle of the fork 53, so that the position of the guide roller 58 can be adjusted to or from the companion guide roller 57 as the conditions of operation demand. Above the supporting r0ller 57, I preferably mount a swinging chute 63, which is connected with an exhaust fan so as to draw off the dust from the belt and the filings from the die.

One of the dies which this machine is adapted to grind is shown in perspective in Fig. 2, and it will be seen to have the thickened base portion 65, which is perfectly flat, and rests on the fiat table 21 while it is being ground, so as to keep the cutting edge 6 in proper relationship to the abrasive belt 36. The outer faces of the dies are considerably rounded, as seen at 67, while the inner faces, as seen at 68, are but slightly rounded.

In use, it will be understood that the turnbuckle 40 is adjusted so as to give the desired and necessary tension to the abrasive belt 36, and the belt is started by closing the isshoved against the belt as indicated in Fig. 5, and with this adjustment, the ad-' jacent surfaceofttl e belt engages the vertical wall of the outer face of the die, as well as the convex surface 67, and rinds off the outer face. After the outer ace is ground off, the frame 44 is adjusted to the position shown in Fig. 6 by turning the handle 51, in which position the grinding side of the belt 36 i in .a more nearly perpendicular position in which it is adapted to coiiperate with the inner side of the die and to grind the face 68. It will of course be understood that the chute 63 is swung out of the way sufficiently so that the die can be placed over the rolls 37 and '57. With the adjustment provided, it will be understood that the position of the guiding rolls and the top supporting roll can be shifted as may be necessary to bring the operating face of the belt to the proper angle to cotiperate with the particular die to be ground.

While I have shown and described my invention as embodied in the form which I at present considr best adapted to carry out its purposes, it will be understood that it is capable of modifications, and that I do not desire to be limited in the interpretation of the following claim except as may be necessitated by the state of the prior art.

What I claim as new, and desire to secure by Letters Patent of the United States, is:

1. In a die-grinding machine, the combination with a main frame having a large, stationary horizontal table thereon on which the dies are moved as they are ground, of an endless abrasive belt running through said table and substantially at right angles thereto, guide rollers for said belt adjacent the table, supporting rollers for the belt, means for rotating one of the supporting rollers to drive the belt, a frame in which the guide rollers are supported, and means for adjusting the guide roller frame along the surface of the table to vary the angle of the belt in accordance with the angles of the sides of the dies adjacent their cutting edges and holding it in the desired position for adjustment.

2. In a die-grinding machine, the combination with a main frame having a horizontal table thereon, of an on less abrasive belt running through said table and substantially at right angles thereto, guide rollers for said belt adjacent th,e ing rollers for the belt, means for rotating one of the supporting rollers to drive the belt, means for adjusting the guide rollers along the surface of the table to vary the angle of the belt in accordance with the angles of the sides of the dies adjacent their table, supportcutting edges, said means consisting of guideways on the table, a roller adjusting frame sliding in said Ways, a screw and nut connected with the roller adjusting frame and the table, and a supporting frame for the guide rollers 'carried by the roller adjusting frame.

3. In a die-grinding machine, the combinationwith a main frame having a horizontal table thereon, of anendless abrasive belt running through said table and substantially at right angles thereto, guide rollers for said belt adjacent the table, supporting rollers for the belt, means for rotating one of the supporting rollers to drive the belt, means for adjusting the'guide rollers along the surface of the table :to vary the angle of the belt in accordance with, the angles of the sides of the dies adjacent their cutting edges,. and means for adjusting the guide rollers to and from each other.

4. In a die-grinding machine, the combination with a main frame'having a horizontal table on the top thereof, of a roller adjusting frame movable horizontally on said table, and having a central opening therein and channels in the opposed faces of said opening, an upper fork supported and guided by said channels, a supporting roller journaled in the top of the fork,a guide roller journaled in the fork beneath .the supporting roller, a lower fork adjustably mounted on the upper fork, a guide roller journaled in the lower fork, a driving roller j ournaled in the main frame, an endless abrasive belt cooperating' with all of said rollers, and means for rotating the driving roller..

5. In a die-grinding machine, the combination With a main ame having a horizontal table thereon, of a swinging belttightening frame pivoted below the table,

a drive shaft journaled in the belt-tightening frame, means for rotating the shaft, a roller suppprting frame supported .in the table above the drive shaft, a supporting roller in the top of the roller supporting frame, guide rollers above and below the adjusting the position of the swinging belttightening frame relative to the ta le to vary the tension of the belt.

6. In a die-grinding machine, the combination with a main frame having a horizontal table thereon, of a swinging belt tightenin frame pivoted below the table, a drive s aft journaled in the belt-tightening frame, means for rotating the shaft, a roller supporting frame supported in the table above the drive shaft, a supporting roller in the top of the roller supporting frame, guide rollers above and below' the table, a supporting roller onthe drive shaft, an endless abrasive belt running over the supporting and guide rollers substantially at right angles to the table, means for aol-.

justing the position of the swinging belttightening frame relative to the table to vary the tension of the belt, and means for adjusting the roller supporting frame horizontally to vary the angle of the belt in accordance with the angles of the sides of the dies adjacent their cutting edges.

In witness whereof, have hereunto set my hand and afixed my seal, this first day of March A. D. 1917.

LE nor B. rnasnn. 1,. 8.]

Witnesses EDWARD H. Loonwoon, J, W. FISHER. 

